JPS588666B2 - alternating current generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an alternating current generator configured to rectify high frequency alternating current and supply low frequency alternating current to a load.

2. Description of the Related Art In order to obtain a small-sized, high-output alternating current generator, a high-frequency generator has been conventionally used to convert its high-frequency alternating current output into a low-frequency alternating current output to supply power to a load.

As this type of alternating current generator, for example, the one shown in FIG. 6 has been proposed.

Figure 6 uses an inductor type high frequency generator.
, 3 and 4 are armature windings, 5 is a field winding, 6 is an exciter winding, γ is an automatic voltage regulator, 8 is a sine wave oscillator, 9 is a filter, and 10 is a load.

SCR1 to SCR4 are silicon controlled rectifiers, T1
and T2 indicate a commutation transformer. The field winding 5 is supplied with a low frequency alternating current of, for example, 50 Hz, thereby generating a high frequency wave whose amplitude is modulated at a low frequency in each armature winding 1, 2, 3, 4.

Silicon controlled rectifier SC during half cycle of low frequency alternating current
R1 and SCR3 are turned on, and silicon controlled rectifiers SCR2 and SCR4 are turned on during the other half cycle.

Then, low frequency AC power is supplied to the load 10, and its pulsation is removed by the filter 9.

An alternating current generator of the type shown in Figure 6 requires a relatively large capacity filter capacitor, a special generator, and a commutating transformer for silicon-controlled rectifying elements. As a result, the entire AC power generator becomes large and relatively expensive.

SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks, and to provide an alternating current generator that can be made smaller and simpler as a whole, and can be manufactured at a lower cost.

Hereinafter, the present invention will be explained with reference to the drawings.

FIG. 1 is an electric circuit diagram showing a part of an embodiment of the AC generator of the present invention, FIG. 2 is a block diagram showing its excitation system, FIG. 3 is a diagram explaining the arrangement of armature coils, and FIG. FIG. 4 is a block diagram showing a transistor base signal generator that controls the power transistors 11 and 12, and FIG. 5 is a diagram showing waveforms at various parts.

1 to 4, 11 and 12 are power transistors, 13 is a series capacitor for tuning, and 14 is a series capacitor for tuning.
is an exciter winding, 15 is an automatic voltage regulator, 16 is a sine wave oscillator, 17 is a field winding, 18 is a transistor base signal generator, 19 is a battery, A1 to C1 and A2 to C2 are three phases. Armature winding, D is diode, G
1 and G2 are the bases of power transistors 11 and 12.

The alternator used in one embodiment of the invention is a commonly used three-phase alternator.

As shown in FIG. 3, three-phase armature windings A1, B1, C1 and A2, B2, C2 are wound around the stator.

Windings A1 and A2 are in phase and in parallel, similarly winding B1
and B2 are also in phase and in parallel, and windings C1 and C2 are also in phase and in parallel.

A low frequency alternating current is supplied to the field winding 17 from a sine wave oscillator 16 .

This frequency is, for example, 50Hz or 60Hz.

The exciter winding 14 takes out part of the output of the alternator.

This winding may be either single phase or three phase.

The voltage across the load 10 is taken out from terminals Y, Y, and an automatic voltage regulator 15 compares this load voltage with a predetermined reference voltage and supplies an output corresponding to these deviations to a sine wave oscillator 16.

Thereby, the magnitude of the output of the sine wave oscillator 16 is set to a magnitude corresponding to the above deviation.

The exciter winding 14, automatic voltage regulator 15, sine oscillator 16, etc. constitute an AC excitation power source.

For example, an alternator rotates at 6000 revolutions per minute, and its armature windings A1, B1, C1, A2, B2, and C2 have 50H.
A voltage proportional to the current flowing through the field winding 17 is taken out from the terminals X, X at both ends of the fold R, in which a high frequency alternating current voltage of, for example, 400 Hz, which is amplitude modulated at 60 Hz or 60 Hz, is generated.

This voltage is applied to the transistor base signal generator 18 as shown in FIG. 4 and converted into a synchronous square wave.

A voltage as shown in FIG. 5 (a) and (c) is applied to the bases G1, G2 of the transistors 11, 12 in synchronization with the output waveform of the diode D (FIG. 5 a).

When the power transistor 11 is in the on state, the output of the three-phase armature winding A1, B1, C1 is the output of the three-phase armature winding A1,
The signal is full-wave rectified by six diodes D connected to B1 and C1, and is supplied to the filter 9 and load 10.

The three-phase full-wave rectified waveform is shown in FIG. 5A.

These six diodes D constitute a full-wave rectifier.

When the power transistor 12 is in the on state, the output of the three-phase armature winding A2, B2, C2 is the output of the three-phase armature winding A2,
The signal is full-wave rectified by six diodes D connected to B2 and C2, and is supplied to the filter 9 and load 10.

These six diodes D also constitute a full-wave rectifier.

As a result, the input waveform of the filter 9 becomes a waveform as shown in FIG. 5-2.

Then, the pulsating component is removed by the filter 9, and the load 10
The waveforms at both ends are as shown in FIG.

As is well known, the pulsation of three-phase full-wave rectification is smaller than that of single-phase full-wave rectification as shown in FIG. 6, and therefore, according to the present invention, the capacity of the filter is reduced. The entire tank can be made smaller and lighter.

Although the above description has been made regarding an example in which a power transistor is used as a control element, a gate turn-off thyristor can also be used as a control element.

Further, the tuning capacitor 13 may be omitted.

As is clear from the above description, according to the present invention, the capacity of the filter can be made smaller than that of conventional filters, no commutating transformer is required since no silicon-controlled rectifier is used, and It is possible to obtain an alternating current generator which has advantages such as being able to use a normal type alternator without the need to use a special high frequency generator as an alternating current generator.

As a result, according to the present invention, it is possible to obtain an AC power generator having a simple and compact circuit configuration and being inexpensive.

[Brief explanation of drawings]

FIG. 1 is an electric circuit diagram showing a part of an embodiment of the AC generator of the present invention, FIG. 2 is a block diagram showing its excitation system, FIG. 3 is a diagram showing the arrangement of armature coils, and FIG. The figure is a block diagram showing the transistor base signal generator that controls the power transistors 11 and 12, FIG. 5 is a diagram showing the waveforms of each part, and FIG. It is a circuit diagram. 9...Filter, 10...Load, 11 and 12...
Power transistor, 13... Series capacitor, 14.
...Exciter winding, 15...Automatic voltage regulator, 1
6... Masahiro wave oscillator, 17... Field coil, 18.
...Transistor base signal generator, 19...Battery, Al, B1, C1, A2, B2, C2...Armature winding, D...Diode.

Claims (1)

[Claims] 1. A three-phase alternating current generator having two sets of three-phase armature windings;
The AC excitation power source supplies an AC excitation current to the field winding of the three-phase AC generator, and the output of the three-phase armature winding of one of the two sets of three-phase armatures is connected to the three-phase a first full-wave rectifier that is oriented to rectify the waves and pass a positive current to the load; and the output of the other three-phase armature winding of the two sets of three-phase armature windings. a second full-wave rectifier oriented to perform three-phase full-wave rectification and provide reverse current to the load; and a second full-wave rectifier disposed between the load and the first full-wave rectifier; a first transistor or gate turn-off thyristor for controlling the forward current flowing to the load; and a second transistor or gate turn-off thyristor disposed between the load and the second full-wave rectifier for controlling the reverse current flowing to the load. a transistor or gate turn-off thyristor; and a control circuit for controlling the first transistor or gate turn-off thyristor and the second transistor or gate turn-off thyristor, the control circuit controlling the AC excitation. The above first cycle has the same period as the output of the power supply.
a first control signal that controls the transistor or gate turn-off thyristor; and a second control signal that controls the second transistor or gate turn-off thyristor that has the same period as the AC excitation power source and is delayed by % period. An alternating current generator configured to generate a control signal.